Charge transfer in low-energy O4+-H and Si4+-H collisions

A theoretical investigation of electron capture processes leading to charge transfer in collisions of O4+ and Si4+ ions with atomic H is undertaken for the energy range 1-1000 eV amu-1. An adiabatic molecular basis set, with the inclusion of appropriate translation factors, is used to describe the collision dynamics. It is found that the charge transfer cross sections are critically dependent on the nature of the ionic core at energies less than a few 100 eV amu-1. A comparison with the experimental results on O4+ - H reveals our interest in the 100 eV amu-1 energy range for testing the theoretical model and verifying the consistency of the experiments. (author)